Indian cities’ levels of air pollution are continuing to rise. Critical contributions to this trend are coming from hidden air pollutants, scientists from the University of Birmingham have revealed.
Using observations from instruments on satellites that scan the global skies every day, scientists were able to build estimated trends for a range of air pollutants from 2005 to 2018, timed to examine rapid development in India and air quality policies in the UK. The findings from these estimates, published in the journal Atmospheric Chemistry and Physics, showed that PM 2.5 — a categorisation of tiny particles or droplets in the air that are two and one half microns or less in width — are the leading contributor to premature death from exposure to air pollution, and nitrogen dioxide (NO2) in Kanpur and Delhi. Alongside this, the air pollutant formaldehyde was found to have increased in Delhi, Kanpur and London.
Study co-author Professor William Bloss, from the University of Birmingham, said, “we were surprised to see the increase in formaldehyde above Delhi, Kanpur and London — a clue that emissions of other volatile organic compounds may be changing, potentially driven by economic development and changes in domestic behaviour. Our results emphasise the need to monitor our air for the unexpected, and the importance of ongoing enforcement of measures for cleaner air.”
As far back as 2018, information gathered by Europe’s Sentinel-5P satellite tracking air quality worldwide showed observations of elevated concentrations of formaldehyde over India. These were deemed a ‘signifier of more general pollution problems’ by Isabelle De Smedt from the Royal Belgian Institute for Space Aeronomy.
Commenting on the findings, she said “the formaldehyde column is composed of different sorts of volatile organic compounds, and the source can be from vegetation — so, from natural origin — but also from fires and pollution.”
Why should formaldehyde be cause for concern
Formaldehyde is from chemicals collectively known as non-methane volatile organic compounds (NMVOCs). It is a highly reactive and toxic chemical, recognised as a Group-1 carcinogen by the International Agency for Research on Cancer.
Research published in Heliyon examining NMVOC emissions from a landfill site in Ahmedabad notes that these compounds ‘play an important role in atmospheric chemistry, and elevated concentrations of some compounds are responsible for air quality deterioration.’ Yet it is the potential health implications that should be cause for concern. Formaldehyde exposure has been linked to increased myeloid leukemia risk, as well as a range of rare noncommunicable diseases such cancers of the paranasal sinuses, nasal cavity, and nasopharynx.
This pollutant has a particular impact on indoor air quality, which is another notable ongoing problem that continues to plight India cities. It is often released as a carcinogen from biomass fuels which is a method familiar with households across the country, particularly for cooking and heating.
India’s air pollution problem
Formaldehyde is now part of a wider story, with pollution remaining a clear and significant problem for India. Many of Indian’s cities now rank almost four times higher than the World Health Organization’s guidelines for safe air quality.
The effects of air pollution in India are damaging both economic development and healthcare. As Health Issues India previously reported, a study conducted by researchers from the Global Observatory on Pollution and Health at Boston College, the Indian Council of Medical Research, and the Public Health Foundation of India found that air pollution accounted for $36.8 billion worth of economic damage to India. Part of this economic loss was attributable to premature deaths caused by air pollution in 2019.
Dr Eloise Marais, associate professor at the University College London Department of Geography, said “measures to tackle pollution take time, so a long and consistent record of observations is vital for assessing the success or inadequacies of current mitigation measures.” Yet all of this serves to underline that more needs to be done in a country that bears a significant burden of the world’s respiratory diseases.
